Question

    Sachin can complete a job in 15 days. Ankit alone can

    complete the same job in 10 days. Sachin works for 9 days and then the remaining job is completed by Ankit. How many days will it take Ankit to complete the remaining job alone?
    A 5 days Correct Answer Incorrect Answer
    B 8 days Correct Answer Incorrect Answer
    C 6 days Correct Answer Incorrect Answer
    D 4 days Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    Sachin’s 1 day work = 1/15 days
    ∴ Sachin’s 9 days work = 9/15 = 3/5days,
    ∴ Remaining work = 1 - 3/5 = 2/5 part of the work.
    Ankit completes 1 work in 10 days.
    ∴ Ankit will complete 2/5 part of the work in `10xx2/5` = 4 days.
    Alternate Method:
    Sachin Ankit
    Time taken 15 10
    Total work = LCM 30 units
    2 : 3
    Sachin's 9 days work = `2xx9` = 18 units
    So remainning work = 30 - 18 = 12 units which is completed by Ankit alone in = 12/3= 4 days

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